System of ventilating railway tunnels or subways.



No, 832,856. PATEN TED 001". 9, 1906.

I w. P. GROOM. I

. SYSTEM OF VBNTILATING RAILWAY TUNNELS OR SUBWAYS.

APPLICATION FILED SEPT. 7. 1905.

3 SHEETS-SHEET 1 WIT/VESSES:

ATTORNEY No. 832,1856, i PATENTED OUT. 9, 1906.

' w. P. GROOM.

SYSTEM OF VENTILATING RAILWAY TUNNELS 0R SU BW'AYS.

' APPLIOATION r ninn 832127. 1905.

' s snnnrs -snnm 2.

WITNESSES: I I 7 INVENTOR .ZMWW ifidkwfirmpg 832,856. l v PATENTED OGT. 9, 1906.

W. P. GROOM. I

SYSTEM OF VE'NTI-LATING RALLWAY TUNNELS OR SUBWAYS.

APPLICATION FILED SEPT. 7, 1905. v

, 3 SHEETS-SHEET 3.

WITNESSES: INVENTOR ATTORNEY UN ITED STATES PATENT OFFICE.

WALLACE PRATT UROOM, OF EW YORK, N. Y.

SYSTEM OF VENTILATING RAILWAY TUNNELS OR SUBWAYS.

Specification of Letters Patent.

Patented Oct. 9, 1906.

Application filedSepteniber '7, 1905. Serial No 277,282.

To all 2071 0111 it may concern:

Be it. known that I, WALLACE PRAT' GRooM, a citizen of the United States, and a resident of Brooklyn borough, New York, in

the county of Kings and State of New York,

'ance s for ventilating railway subways and 0 tunnels; and it has r its object to so construct and arrange flues or ducts for influx of fresh and pure air and for efl'iux of spent or vitiated air and to so construct and attach appliances to a car of any train to be run through such tunnel or subway and also such appliances to the tunnel or subway itself as to cause the movement of trains therein to aid and increase the influx of fresh airto and f fefiiux of vitiated air from such tunnel or sub- Way, which influx and efflux will take place at all times, even in intervals when moyemerit of trains therein is intermitted. The terms subway and tunnel are herein ufipd. as ,signifying substantially. the same t 11g. v

My invention partly consists in a peculiar arrangement and construction of air ducts or fluesfor inflow and outflow of air to and from asubway or tunnel.

The invention also consists in appliances,

for substantially dividing the space in a tunnel or subway into distinct longitudinal passages for the circulation of, air therein longitudinally in sections where the ventilatin ducts or fines are located in relation withsai space.

The invention further consists in the attachment of wings or fans to a car of each train which passes through such tunnels or subways or which ply therein, whereby the movement of air by the motion of the train is increased and intensified, and also, as part of the general system, in the special construction and means of attachment of such wings or fans to a car or cars.

Figure 1 of the drawings represents a vertical longitudinal section of a subway em bodying my system of and appliances for ventilation, the section bein on line a; w in Fig. 2. Fig. 2 is a plan of t e same with a portion of the superimposed earth and a portion of the roof removed. Fig. 3 is a partial cross-section made on line 31 y in Fig. 1. Fig. 4 is a detail showing means employed for dividing the tunnel longitudinally into distinct passages for air. Figs. 5, 6, and 7 are respectively a side elevation, a front elevation, and a plan of a spring-hinge attachment, whereby the wings or fans hereinarter described may be fastened in working position on a can. Fig. 8 is an enlarged view of a wing or fan, showing a method of attaching the same to the spring and to a car.

The tunnel or subway A, Figs. 1, 2, and 3, is shown in these drawings as constructed with a sheathing of metal B on the under side of its roofand metal sheathing B on the inner surface of its sides, the roof being supported by vertical metal posts a and girders the tunnel having parallel railway-tracks therein, the rails being shown at 0 supported on ties d.

A car Cis shown in side elevation Fig.175

-1, in plan in Fig. 2, and in front elevation m i. right in the drawing, and the movement of the car being always in the same direction for any one track.

, 3 The construction of the car may be of any type, either adapted to electric propulsion or propelled by any kind of powerwhile passing through the tunnel or subway, and the construction of the tunnel may be of any kind other than that shown as an excavation through solid rock, amason-work structure, &c.for, although the action of my invention is-partially dependent upon a tunnel or subway and a car or train of cars running therein, it is wholly independent of any particular type of tunnel or car except that the front end of the car is assumed to be closed, as shown in Fig. 3.

I have shown the tunnel or subway as containing two parallel or substantially parallel railway-trac s; but my invention is entirel independent of the number of tracks and 18' adapted to use 11 a tunnel. wherein o "a single track is em lo'yed or in a subway hav ing any practicablb number of tracks.

Extending to a considerable distance rearward relatively to the direction in which the car uniforml runs is a duct E for outflow of vitiated air iiom thcinterior of the subway. Extending forward to a considerable distance relatively to the direction in which the car uniformly runs is a duct F for inflow of fresh cooler air. It is found by experience that for much of the time when a subway is used for passenger trafiic the air therei IIO ' that of the exterior atmosphere. the case, an outfiowing current of spent r in. air-currents created by uniformly ofhigher mean temperature than This being tern erature, but also will greatly accelerate out ow of vitiated air and inflow of fresh air through force generated by motion of a car or train of cars approaching the open mouth of the vitiated-air duct and again rapidly moving away from the mouth of the freshair duct, as will be more fully explained hereinaft'er.

In the drawings the portion of the airducts contained in the tunnel or subway are shownas extending downward at the side of the track nearly to the bottom or floor of .the subway,with easy bends where they pass up through the sheathing B, from which they extend upward through the superimposed earth G to an elevation sufiicient to establish a positive upward current in the vitiated-air duct and a positive downward current in the fresh-air duct, the currents within limits being stronger proportionately to the said elevation, as is the case with ordinary furnacechimneys. As the diiierences of temperature establishing the currents are small in comparison withthe ordinary difierences of temperature which induce the draft of furnacechimneys, the fiow ofair in the ventilating-ducts E and F will at best be sluggish as com ared with ordinary furnace-draft,

but wil be much accelerated by the movement of the car or train of cars when the latter are passing at the usual speed through the subway, as more fully hereinafter ex lained.

The vitiated-air duct and the esh-air duct may be placed at different oints but I prefer to bring them close togetl ier and from where the pass'up through the sheathing to contract tiiem longitudinally and widen them laterally with respect to the direction of the tunnel, as shown in section and plan, in such manner as to merge them into a single stack H above the ground G, the partition d, Fig. 1, separating the fresh-air duct E from duct F, and to extend theduct E to an elevation considerably highenthan the trip of the fresh-air duct, as clearly indicated in the drawings. The practicable height of each of these ducts will depend more or less upon conditions of practice; but the fresh air duct should wherever possible rise to a, point which is comparatively .free from dust, and the vit a-ted-air duct should extend to a point cons1derably higher, not only for strengthening such differences of shown in mouth of the fresh-air current. have passed the ventilating-ducts the pressure thus augments the flow,

the current therein, but for discharging the vitiated air at a point which will practically exclude the possibility of any intermingling I of the discharged air and that entering the cold-air duct. Both ducts should be provided with suitable hoods for preventing the entrance or rain and snow. These hoods are indicated at h and h, Fig. 1.

By reference to Figs. 1 and 3 it will be seen that the mouths m of the ducts are in this example of my invention oblong in contour, the object sought being to obtain as much area of opening as possible within the subway, and in the construction of the ducts Figs. 2 and 3, Where. they merge into the stack H, the object is to avoid con tracting the cross-section area of the duct as much aspracticable in order to secure as large a volume of flow as practicable into or out of the mouths m of said ducts.

As the car or train of cars approach at speed toward the mouth of duct E they generate pressure in the tunnel in advance of their progress, setting up a strong current in the direction of their motion. A portion of this current presses against the open mouth of duct E, enters the duct, and materially accelerates the upward flow of air through said duct. Conversely, the current ahead of the car or cars blowing over and not into the duct F in the tunnel produces a partial vacuum in this duct, and this accelerates the ,fiow through the duct into the subway This action is ased on the long-recognized fact that a forcible current of air blown along over the outer Walls of a 'tube or air-duct in the direction of its len th and passing over an open end of the tn e, while its other end is not sub ected to the action of the outer current, produces a flow of air in the tube in the direction of the outer Also after the car or train of cars is materially lessened in the tunnel immediately behind and to a considerable distance in the rear of the train. The exterior air then taking the path of least resistance-to wit, the shorter fresh-air duct-therefore continues to flow into the subway after the passage of the train. The action explained which in absence of the movement of cars in the subway would be established by temperature difierences anil resulting specific gravity difierenees on 1% is obvious that the action described will be more pronounced the more nearly it can be confined to a single and distinct longitudinal passage in a subway. Where such a tunnel contains more than one parallel track and posts a are ranged at set distances between the tracks, it will be necessary in order to insure best results to interpose a septum between each two adjacent posts for a considerable distance on each side ofthe venti- I30 the lower margin by a bar It or otherwise secured at the bottom to hold them-in substantially vertical position when pulled down, as shown in Fig. 4; but I make no claim herein for such septum or equivalent device, reserving my claim thereto as the subject-matter of a separate application. It is obvious, also, that-the lower parts of the air-ducts E and F may be varied in shape to adapt them to tunnels or subways of different cross-sections, widths, and depths; but whatever available space the arts of these ductscontained in the tunne or subway may occupy it is essential that the mouths of those parts of the vitiated-air ducts in the tunnel shall face toward and the mouths of those parts of the fresh-air ducts in the tunnel-shall face away from a preaching cars. It will also be apparent tl 'iat the effective production of increased pressure in advance of moving cars in the tunnel will be favored'by making the front surfaces of the leading cars of trains conform in. shape as closely as practicable to they should be as uniform as existing conditions will permit.

I will now describe ineans'for movably and detachably fastening the wings or fans to the car. Although the body of the fan L, Fig. 8, is there shownuin face iew to be of root ngular contour, it ma y ha h tween the car and the inner surfaces of the tunnel.

The bodies of the fans made be made'of thin sheet metal or cloth stretched over a light wire frame or paper glued upon a skeleton of bamboo after the manner of Japanese -fans or of any other material whatever which combines sufficient strength with lightness and resilience and sufficiently impervious to the passage of air through the texture thereof. The fan-bodies may be each provided with a shank n for attachment to'a spring hinge 7) of special construction, yet to be described, in such manner that their faces stand normally at right angles with the vertical sides of the car. T he spring-hinge attachment is preferable, as it enables the body of the fan to pass easily,

ve any conto r -,which is required to enable a set of these fans to fill the larger part of the sectional spacebeany obstructions while the car is moving should any object temporarily constitute an obstructionfbut this kind of attachment is not essential to the general operation of the wings or fans,wl1ich -by preventing a large part of the rearward sllp of air ast the car produce a stronger pressure and ow of air in advance, as well as a greater reduction in pressure in the rear thereof.

The spring-hinge I prefer to emplo is shown in detailin Figs. 5, 6, and 7. t is composed of a furcated metal piece g, which has a socket '0 at the top for reception of the shank n, riveted or otherwise suitably fastened to the margin of the body L of the fan,

as shown in F ig. 8. Said socket e is provided with a set-screw v for clamping shank it fast when inserted in the socket. The body of the fan may thus be attached to or detached from the spring-hinge without removing the latter from its permanent at.- tachment, hereinafter described. In the recess s is fitted under the clamping-block t the upper end of a flat spring s, which is firmly clamped and heldby a rivet s, which passes through q, s, and t. The lower end of s is formed into a cylindrical loop which reaches to and bears upon the surface of that part of the bracket or foot-piece t which lies between the furcations of the piece q. The normal relative positions of the parts are shown in full outline in Figs. 5 and 6, the normal position of spring .5 being shown partly in dotted outline in Fig. 5. When the furcated piece g is turned on its pivot t toward the left, as shown in dotted outline in Fig. 5, the spring is bent as shown, and its resilience forces q back into normal position when g is left free to move. A corresponding action of the spring takes place when 9 is turned on its pivot toward the right. Thus the spring 8 acts to restore g to its norm al relative positionthat is to say, to a position at right angles with the foot-piece twhenever g and its socket v are swung from a line vertical to the foot-piece, and they hold a fan L with its shank n inserted and clamped in said socket, as shown in Fig. 8, in such position whenever the movement of the fan is not resisted by temporary obstruction in addition to the resistance of air against its face, the spring being of a strength to hold the body of the fan in position without material deflection when the ear carrying it is in motion at normal speed.

Year the front platform of the car or else where, as convenient, bars W, Figs. 1, 2, and 3, of suitable material, either Wood or metal, are secured to the'body of the carfand to these the foot-pieces t of-the spring-hinges are attached.

The station-platforms of a subway extend laterally out toward the track, so as to leave very little space between their outer margins and car-platforms standing adjacent which cars or thereto, as shown at B, Fig. 3, where R represents a section of a station-platform whereon passengers walk to the car-platform R. Contact of the wings or fans with the projecting edge of such station-platforms is prevented by leaving a space between the fan below the level of the station-platform and the fanabove said level, as clearly shown in Fig. 32

To regulate the inflow of cold air in very cold weather andto prevent the tunnel from becoming uncomfortably cold, I place a damper D, Figs. 1 and 2, in the fresh-air duct.

What I claim as my invention, and desire secure by Letters Patent, is as follows:

to 1. The combination with a subway or railway tunnel containing a-railway -track, of a said subway or scribed and for purp 2. The combination wit way tunnel containing a railway-track, of a discharge air-duct, and an air-supply duct, the openings of said ducts in said subway or tunnel facing in opposite dlrections, the airsupply duct facing toward the direction in Fwhich cars or trains are desi ed'to run in said subway or tunnel, and t e ducts being extended up through the root of the subway or tunnel, substantially as and for the purposes set forth. v

3. The combination with a railway subway ortunnel containing a railway-track, of a wa wtunnel, containing fresh-air duct and a vitiated-air duct, the openings of said ducts within the subway or tunnel facing inopposite directions, the airsupply duct facing in the direction the cars are designed to run in said subway ortunnel, and the ducts being extended up through the roof of said tunnel, the vitiated-air duct beto a greater height than the substantially as described.

4. T is combination with a subway or raila railway-track, and

,withirisaid tunnel an -ing a damper,

acar or cars, of a fresh-air-supply duct, and

' a vitiated-air-discharge duct,'bothducts having openings within said subway or tunnel, said openings facing in' opposite directions, the opening of the fresh-air-supply dag, acing toward the direction cars are designedto run in said subway or tunnel, and both ducts above the subwa or tunnel being merged into a single stac substantially as and for the purposes specified.

- 5. As part of a system of ventilation for railway tunnels or subways, or more railway-tracks, and cars designed for running in specific direction or directions, on saidv track ortracks, said tunnel being provided with a fresh-air-supply duct, having I opening facing toward the direction in which t e car or train of cars is designed to fun, on any contained track, and provided-with a vitiated-air-discharge 'duict, having within said. tunnel or subway an in an opposite. direction from".

opening facing ghat in which the opening of said supply-duct aces; and extending laterally from, the body of a cardesigned to run in said railway tunnel or subw ay, substantially as and for the purposes described. 6. The combination with a railway suba ay or tunnel, containing a railway-track, of a fresh-air duct and a vitiated-air duct, the

openings of said ducts within the subway or tunnel facing in opposite directions, the airsupply duct facing in the direction cars are designed to run in. said subway or tunnel, and the ducts being extended up through the roof of said tunnel, he vitiated-air duct being ex tended up to a greater height than the airsupply duct, and the fresh-air duct containsubstantially as and for the purposes set forth.

Signed at Brooklyn, (New York city,) in the county of Kings and State of New York, this 28th day of August, A. D. 1905.

WALLACE PRATT (moon.-

Witnesses z C. TURNER, M. E. DEAN.

containing one 'of'a set of wings or fans attached 'to,;, 

